diff --git a/requirements.txt b/requirements.txt
index 5a0517d..1f6ede7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,7 +9,7 @@ codecov==2.0.5
 
 # NLP
 numpy==1.13.3
-PyYAML==3.12
+PyYAML==5.4
 nltk==3.2.5
 scikit-learn==0.19.1
 scipy==1.0.0